Tremors are involuntary, rhythmic muscle contractions causing shaking or trembling movements, often in the hands. They can also affect the arms, legs, head, vocal cords, and torso. While tremors can be constant, they may also occur intermittently, presenting significant challenges in daily activities such as writing, eating, or dressing. The presence of tremors can arise independently or as a symptom of another underlying disorder.
Understanding Tremors After Stroke
Post-stroke tremors are rhythmic, involuntary shaking movements affecting various body parts. They differ from other involuntary movements like muscle spasms or clonus due to their rhythmic nature and lack of trigger by stretching. While tremors can be a symptom of conditions such as Parkinson’s disease, those linked to a stroke originate from damage within specific brain regions.
Strokes can cause tremors by disrupting brain motor control pathways, especially when damage occurs in areas like the thalamus, basal ganglia, cerebellum, or brainstem. For instance, cerebellar damage, crucial for coordinating voluntary movements, can cause intention tremors that worsen during purposeful actions like reaching. Damaged basal ganglia, involved in voluntary motor control, can lead to resting tremors.
Several types of tremors may manifest after a stroke:
- Intention tremors are characterized by shaking that increases as an individual attempts a targeted movement.
- Postural tremors appear when a person holds a position against gravity, such as extending their arms.
- Holmes’ tremor, also known as rubral or midbrain tremor, is a complex type that can include resting, postural, and kinetic components, often appearing weeks to months following a stroke.
- Palatal tremors, involving rapid contractions of the soft palate, are less common but can also occur after strokes affecting the brainstem or cerebellum.
The Potential for Tremor Improvement
Post-stroke tremor prognosis varies; some individuals experience improvement or resolution, while others contend with persistent symptoms. Tremor reduction likelihood depends on factors like the affected brain region, damage extent, and tremor type. For instance, intention tremors linked to cerebellar lesions have shown recovery within one to eight weeks in some cases.
Though challenging, post-stroke tremors are not highly prevalent, affecting approximately 1-4% of stroke survivors. Many post-stroke tremors are self-limiting, resolving spontaneously. Studies indicate that over 90% of post-stroke tremors may resolve within six months. Approximately 28% of patients have reported complete disappearance of their tremors, with an additional 64% experiencing partial resolution.
Rehabilitation engagement also influences improvement potential. Consistent therapy participation can help the brain adapt and reduce tremor severity. While improvement is possible, recovery extent varies, requiring realistic expectations.
Approaches to Managing Tremors
Managing post-stroke tremors often involves tailored strategies, especially when they do not fully resolve. Pharmacological interventions primarily reduce tremor severity. Prescribed medications include beta-blockers (e.g., propranolol), anti-seizure drugs, and tranquilizers. For specific tremor types, such as Holmes’ tremor, clonazepam, valproate, levetiracetam, or levodopa may be considered. Botulinum toxin injections can also be used for localized tremors, like palatal tremors.
Rehabilitative therapies improve function and manage tremor impact on daily life. Physical therapy enhances strength, coordination, and muscle control through targeted exercises, promoting neuroplasticity (the brain’s ability to reorganize itself). This retrains the brain to send more accurate signals, potentially improving coordination and reducing tremor.
Occupational therapy plays a role in helping individuals adapt to and manage tremors during everyday activities. Occupational therapists can recommend and teach the use of adaptive equipment, such as weighted utensils, specialized pens, or cups with stabilizing features, to enhance functionality. They also provide guidance on proper body mechanics and posture, which can help minimize the effect of tremors. For tremors affecting communication, specific techniques may be explored.
In cases of severe and persistent tremors that do not respond to other treatments, surgical options like deep brain stimulation (DBS) may be considered. DBS involves implanting electrodes in the thalamus, a brain region involved in tremor generation, to deliver electrical pulses that help disrupt abnormal signals. Additionally, lifestyle adjustments, including stress management and relaxation techniques, can be beneficial, as stress and anxiety often exacerbate tremors.